Oreochromis mossambicus
Oreochromis mossambicus (''Mozambique tilapia)' Kingdom: '''Animalia Phylum: Chordata Class: Actinopterygii Order: Cichliformes Family: Cichlidae Genus: Oreochromis Species: Oreochromis mossambicus Environment: milieu, climate zone, depth range, distribution range: Freshwater; brackish; benthopelagic; amphidromous; depth range 1 - 12 m. Tropical; 17°C - 35°C; 11°S - 31°S, 19°E - 41°E. Distribution: Africa: Lower Zambezi, Lower Shiré and coastal plains from Zambezi delta to Algoa Bay. Occurs southwards to the Brak River in the eastern Cape and in the Transvaal in the Limpopo system. Widely introduced for aquaculture, but escaped and established itself in the wild in many countries, often outcompeting local species. Several countries report adverse ecological impact after introduction. Size, weight, age: Max. length: 39 cm, common length: 35 cm; weight: 1.1 kg; age: 11 years Short description: Diagnosis: snout long; forehead with relatively large scales, starting with 2 scales between the eyes followed by 9 scales up to the dorsal fin. Adult males develop a pointed, duckbill-like snout due to enlarged jaws, often causing the upper profile to become concave, but upper profile convex in smaller specimens. Pharyngeal teeth very fine, the dentigerous area with narrow lobes, the blade in adults longer than dentigerous area; 28-31 vertebrae; 3 anal spines; 14-20 lower gill-rakers; genital papilla of males simple or with a shallow distal notch; caudal fin not densely scaled; female and non-breeding male silvery with 2-5 mid-lateral blotches and some of a more dorsal series; breeding male black with white lower parts of head and red margins to dorsal and caudal fins. Biology: Adults thrive in standing waters. Inhabits reservoirs, rivers, creeks, drains, swamps and tidal creeks; commonly over mud bottoms, often in well-vegetated areas. Also found in warm weedy pools of sluggish streams, canals, and ponds. Most common in blind estuaries and coastal lakes, but usually absent from permanently open estuaries and open sea and from fast-flowing waters. Normally not found at high altitudes. Able to survive extreme reduction of temporary water bodies. Highly euryhaline. Grows and reproduces in fresh-, brackish and seawater. Can be reared under hyper-saline conditions. Tolerates low dissolved oxygen levels and can utilise atmospheric oxygen when water oxygen levels drop. Mainly diurnal. May form schools. Omnivorous, feeds mainly on algae and phytoplankton but also takes some zooplankton, small insects and their larvae, shrimps, earthworms and aquatic macrophytes. Juveniles carnivorous/omnivorous, adults tend to be herbivorous or detritus feeders. Large individuals have been reported to prey on small fishes, and occasionally cannibalise their own young. Exhibits considerable plasticity in feeding habits as well as in reproductive biology. Polygamous, maternal mouthbrooder. Reaches sexual maturity at 15 centimeter length, but stunted fish may breed at 6-7 centimeters and at an age of just over 2 months. Fecundity high. Extended temperature range 8-42 °C, natural temperature range 17-35°C, with salinity-dependent difference in temperature tolerance. Somewhat aggressive toward other species. Marketed fresh and frozen. Excellent palatability, with small head and large dress-out weight, and filets without small bones. Used extensively in biological, physiological and behavioural research . Translocated and introduced for aquaculture, sport fishing, stocking man-made lakes and biological control of nuisance plants and animals . Eurytopic; a most successful and vagile invader. Life cycle and mating behavior: ?''' ''Main reference:'' '''Trewavas, E., 1982. Tilapias: taxonomy and speciation. p. 3-13. In R.S.V. Pullin and R.H. Lowe-McConnell (eds.) The biology and culture of tilapias. ICLARM Conf. Proc. 7. IUCN Red List Status: NEAR THREATENED (''NT)' '''CITES: Not Evaluated CMS: Not Evaluated Threat to humans: Potential pest Human uses: Fisheries: highly commercial; aquaculture: commercial; gamefish: yes; aquarium: commercial. Category:Cichlidae, Cichlids